Spark Plugs
Find Spark Plugs for your vehicle
Enter your reg and we'll show you only parts that fit — no guesswork.
Don't know your reg? Find manually
- ✓ Free delivery on orders over £40
- ✓ UK stock, dispatched from Northampton
- ✓ Filtered to your specific vehicle from DVLA data
Browse all Spark Plugs
- Bosch Engine Spark Plug 0 242 140 530 £7.99
- Bosch Engine Spark Plug 0 242 140 560 £11.99
- Bosch Engine Spark Plug 0 242 135 517 £18.99
- Bosch Engine Spark Plug 0 242 140 535 £11.99
- Bosch Engine Spark Plug 0 242 222 505 £7.99
- Bosch Engine Spark Plug 0 242 140 519 £7.99
- Bosch Engine Spark Plug 0 242 140 514 £12.99
- Bosch Engine Spark Plug 0 242 145 571 £15.99
- Bosch Engine Spark Plug 0 242 135 811 £68.99
- Bosch Engine Spark Plug 0 242 145 612 £14.99
- Bosch Engine Spark Plug 0 242 145 535 £11.99
- Bosch Engine Spark Plug 0 242 145 510 £12.99
- Bosch Engine Spark Plug 0 242 135 801 £17.99
- Bosch Engine Spark Plug 0 242 140 806 £54.99
- Bosch Engine Spark Plug 0 242 145 555 £15.99
- Bosch Engine Spark Plug 0 242 135 813 £24.99
- Bosch Engine Spark Plug 0 242 140 521 £12.99
- Bosch Engine Spark Plug 0 242 140 557 £14.99
- Bosch Engine Spark Plug 0 242 140 523 £10.99
- Bosch Engine Spark Plug 0 242 140 515 £11.99
- Bosch Engine Spark Plug 0 242 135 559 £14.99
- Bosch Engine Spark Plug 0 242 140 566 £16.99
- Bosch Engine Spark Plug 0 242 140 802 £21.99
- Bosch Engine Spark Plug 0 242 135 553 £13.99
About Spark Plugs
NN4 Online stocks a wide range of spark plugs from established manufacturers including Bosch and Denso. Enter your registration above and we'll narrow the list to spark plugs that match your vehicle in the TecDoc catalogue. We always recommend confirming the part dimensions against your existing component before fitting, as specifications can vary between trim levels and engine variants.
All stock dispatches from our Northampton warehouse with free standard delivery on orders over £40 to most UK mainland locations. Browse the full spark plugs catalogue below, or use the registration lookup to filter to parts matched to your vehicle.
Frequently asked
How do I know a part will fit my car?
Enter your registration above and we cross-check against the TecDoc catalogue to narrow the list to spark plugs listed against your vehicle. Specifications can still vary between trim levels and engine variants, so we recommend confirming the part dimensions against your existing component before fitting.
What brands do you stock?
We stock established manufacturer brands sourced through trade channels. The brand row at the bottom of this page shows which manufacturers we carry for spark plugs. We don't sell unbranded parts.
How quickly will my order arrive?
Most orders dispatch from our Northampton warehouse within 1–2 working days. Free standard delivery on orders over £40 to most UK mainland locations.
What if the part doesn't fit?
Please check our returns policy for the current terms. If you're unsure about fitment for your specific vehicle variant, please contact our team before ordering using the details at the bottom of the site.
Can I check fitment before ordering?
Yes — every product page shows whether the part is listed against your selected vehicle. Where multiple sizes exist for the same vehicle, the dimensions are shown so you can compare against your existing part. If you're unsure, contact our team for help confirming the right option.
About Spark Plugs
Our spark plugs range is built from established UK suppliers and trusted aftermarket brands. Each product is mapped against OE/OEM references and TecDoc ktype data so the reg-lookup above filters to only the parts that fit your specific make, model, engine and trim.
Enter your registration to see exact-fit options — or browse by brand using the tiles above. The full catalogue covers most major makes and models on UK roads, with same-business-day dispatch on stock items ordered before 2pm.
When to replace your filters
Filters are service-interval parts — oil, air, fuel and cabin filters all have manufacturer-specified replacement intervals, typically every 15,000-30,000 km or annually, whichever comes first. Skipping a filter change can cost more in engine wear and reduced fuel economy than the part itself.
Common signs a filter needs changing
- Reduced acceleration or fuel economy — restricted air filter limiting intake.
- Engine misfires — a clogged fuel filter starving the injectors.
- Cabin air feels stale or musty — pollen filter saturated.
- Oil pressure warnings — restricted oil filter, or a bypass valve issue.
Choosing the right filter
Filters are tightly engine-specific — even within the same model year, different fuel-system variants use different parts. Our reg-lookup maps to the exact OE part number for your engine code, so you can be confident the cross-reference works before you order.
Why buy from NN4 Online
- Reg-lookup fitment — see only the parts mapped to your specific vehicle.
- UK warehouses — most stock items dispatch same business day on orders before 2pm.
- Established brands — the brand tiles above are the full list available in this category.
- Standard returns — handled per our returns policy linked in the footer.